Additional intracrine imbalances are described in bone diseases, such as higher androgen reducing 17βHSD activity in benign vs. malignant tumors, declines of CYP19A1 from normal bone to osteosarcoma and expression of SULT1E1 in the majority of the skeletal benign and malignant lesions, originated in bones or from primary tumors elsewhere (Svoboda et al., 2007). This evidence concerns the gene CYP19A1 and osteosarcoma.